About Daylio
Daylio is a mood diary from Relaxio s.r.o. Each entry is a mood rating plus taps on activity icons (sleep, exercise, work, people and so on), with an optional written note. The app turns these into calendars, mood charts and simple activity-mood links, and can export PDF or CSV reports. There is no account: the developer says entries are stored only on your device, with optional backups to your own Google Drive or iCloud that it cannot access. The free version stays unlimited for basic logging; Premium adds more statistics and customization. It is a self-monitoring tool, not treatment, and we found no published study of its effect on mood.